We sometimes call the lion "the king of the forest", because it is stronger and more dangerous than other animals. It can 1 faster than many animals and hunt the best. It is the highest animal in the 2 food chain.

    In the sea, the shark is one of the animals at the top of the food chain. It can swim faster than 3 other sea animals, and it can use its big teeth to eat them.

    What is at the top of the world's food chain? People are! We are not the biggest or fastest, but we are the 4. We could not run faster than cheetahs(猎豹), so we 5 cars and now we can move the fastest. We could not fight better than lions, so we invented guns. Now we can hunt the best.

    People's inventions are clever, but they can be 6, too. For example, people built 7, and now they make the air and rivers dirty. This can make terrible changes. Dirty rivers kill fish. 8 bears cannot eat the fish. If we kill one part of the food chain, other parts also will die. Remember that we are a part of the food chain, 9 we are in danger, too! If we protect animals, we are protecting 10! We could and we should do something for the world!

    We all cry for water when we are thirsty. But do you know, in very hot, dry weather, plants also make very low sounds as if they are crying for help?

    You see, in a plant's stem there are several hundred "water pipes" that bring water from soil all the way up to the leaves. When the ground turns dry, it becomes harder and harder for plants to do this.

    In very hot days, plants have to get any water that they can get.

    Scientists Robot Winter has found out that when plants can get no water, their "water pipes" snap(发出声音). When that happens, the whole plant vibrates(颤动) a little.

    Robot knows that healthy, well-watered plants are quiet. He also knows that dry plants are many insects' favorites and they often attack(袭击) them. How do the insects know which are healthy plants and which are not? Robot thinks that the insects may hear the plants "crying" and they may come to kill them.

Xian Xinghai is a very famous musician in China. He has written many great pieces of music. In his short life, he wrote nearly 300 songs and an opera. 

Xian was born in Panyu, Guangzhou in 1905. Because his father died before he was born, Xian had to move from place to place with his mother. He began learning to play the violin when he was 20 years old. At first, his violin was so cheap and in a poor quality that he could not play it well. His friends laughed at him. However, Xian did not stop practicing and soon showed his talent. In 1931, he became the first Chinese student who studied in a special music school in Paris. Before he left, Xian became the school's best student and won several prizes for his talent. 

In 1935, he got back to China and helped fight against the Japanese army. Later, he came to Yan'an to teach music at a college. Although there were no pianos in Yan'an at that time, Xian still wrote some of his most important music there, including The Yellow River Chorus, his most famous work. 

In May 1940, Xian Xinghai went to the Soviet Union(苏联) to write music for movies. Life there was so hard that he got very sick. Later he died of a lung illness on October 30, 1945, aged only 40. 

Xian Xinghai is such a great man and his music will live on in people's hearts forever. 

Hi, I'm a student in Beijing. I'm1 here, so I don't have many friends now. Can you be my 2 ?

Now let me introduce(介绍) myself. I'm Bella. I'm thirteen. I'm good at English, so I can3 you with it.

My favourite colour is 4 , so I have many blue things. Look,5 bag is blue. My favourite 6 of the week is Friday, because we have a music class that day. I love music. I listen to music after school. I also like to 7 songs in my free time. My friend Lena thinks I'ma good writer.

My favourite sport is 8 . I can play it well. Do you like playing it,9 ? Tomorrow is 10 and I don't go to school. We can meet and play table tennis. My 11 is 564736. You can call me. And I also like swimming on 12 days, because it can make me cool. We can also go swimming together 13 summer.

That's all about me. If you want to 14 more about me, you' re welcome to call or write to me! 15 for listening to(听) me.

 As China grows stronger and stronger, more and more foreign people have started to learn Chinese. However, many of them have discovered it is very difficult to learn Chinese, especially at home without anyone' s help. A famous AI company(人工智能公司) in China has paid attention1 the problem. It has developed a smartphone app called iFlyChinese(全球中文学习平台).

 With the help of AI-based voice technologies, the app users can learn Chinese 2 and quickly. When users speak into the app in their own languages,3 app can turn the voice messages into Chinese. When 4 read sentences in Chinese, it will give them feedback(反馈). It can also correct(更正) their mistakes in their pronunciation 5 grammar. Finally, it will provide cards with words or pictures for users to practice and 6 .

 With the help of the app, many users have got the 7 to speak and use Chinese. Henry is one of them. He8 to learn Chinese two years ago. He has made great progress by 9 the app. Now he can have conversations with his friends in Chinese.

 The app has been very popular in foreign countries since it was developed. Now 10 people in more than one hundred countries are using the app.